The Department of Justice has announced that it believes courts should apply heightened scrutiny to laws that classify people based on sexual orientation – particularly the Defense of Marriage Act. In a letter sent on Feb. 23 to Speaker John Boehner (R-Ohio), Attorney General Eric Holder writes that, because of this decision, the department will no longer defend Section 3 of DOMA, which defines ”marriage” and ”spouse” as referring only to opposite-sex marriages.

The issue was raised, Holder explained in a statement released along with the letter, because Section 3 of DOMA has been challenged in the [U.S. Court of Appeals for the] Second Circuit, ”which has no established or binding standard for how laws concerning sexual orientation should be treated.” Under the Equal Protection Clause of the 14th Amendment – applied to the federal government through the Fifth Amendment – all laws that classify people into groups receive a level of scrutiny: rational basis, which is the lowest form of scrutiny; heightened scrutiny; or strict scrutiny.

The U.S. Supreme Court has not made a determination about the level of scrutiny to apply to sexual orientation classifications, even in the two cases in which it struck down anti-LGBT laws – Romer v. Evans and Lawrence v. Texas.

The cases in question – both filed on Nov. 9, 2010 – were brought by the ACLU in New York and the Gay & Lesbian Advocates & Defenders in Connecticut. The Justice Department’s deadlines for responding to the ACLU case, Windsor v. United States, and the GLAD case, Pedersen v. Office of Personnel Management, were approaching in coming weeks.

As Holder details in the memorandum to Boehner, the Justice Department had defended DOMA in previous cases in California, Florida, Massachusetts and Washington. But, with Windsor and Pedersen, Holder said in the statement, ”the Administration faces for the first time the question of whether laws regarding sexual orientation are subject to the more permissive standard of review or whether a more rigorous standard, under which laws targeting minority groups with a history of discrimination are viewed with suspicion by the courts, should apply.”

In his letter to Boehner, Holder details the four factors laid out by the U.S. Supreme Court for application of heightened scrutiny and writes that the president, given Holder’s recommendation, concluded that ”[e]ach of these factors counsels in favor of being suspicious of classifications based on sexual orientation.”

After making the determination that heightened scrutiny should apply, Holder wrote in the statement, ”The President has also concluded that Section 3 of DOMA, as applied to legally married same-sex couples, fails to meet that standard and is therefore unconstitutional. Given that conclusion, the President has instructed the Department not to defend the statute in such cases.”

Holder noted that he agrees with the president’s decision.

Roberta Kaplan, a partner at Paul, Weiss, Rifkind, Wharton & Garrison LLP and co-counsel with the ACLU in Windsor, told Metro Weekly of the news, ”In one sense, it’s a historic day and a momentous decision by the president and the Justice Department.

”In another sense, it’s not a surprising decision [because] we said that the government was going to have a very hard time justifying” the differential tax treatment faced by her client, Edith Windsor, ”simply by virtue of the fact that she was married to a woman and not to a man.”

In the White House press briefing on Feb. 23, White House spokesman Jay Carney was asked about the decision. Repeatedly drawing a distinction between the president’s personal or policy view and the legal decision, he said that the administration, having alerted Congress to its decision, would assist ”Congress or members of Congress” who wish to defend the law.

Although the decision announced on Wednesday was specific to the Windsor and Pedersen cases, the memorandum asserted that ”pursuant to the President’s instructions, and upon further notification to Congress, I will instruct Department attorneys to advise courts in other pending DOMA litigation of the President’s and my conclusions that a heightened standard should apply, that Section 3 is unconstitutional under that standard and that the Department will cease defense of Section 3.”

Among the cases this decision could impact are Gill v. Office of Personnel Management and Massachusetts v. United States, both of which are pending in the U.S. Court of Appeals for the First Circuit, and Golinski v. Office of Personnel Management, a case pending in the U.S. District Court for the Northern District of California.

It was not immediately clear how the Justice Department would apply the ”heightened scrutiny” determination to other cases involving sexual orientation classifications, including the appeal in Log Cabin Republicans v. United States. The Justice Department’s brief in that case is due to the U.S. Court of Appeals for the Ninth Circuit on Friday, Feb. 25.

The letter sent to Boehner Wednesday is required by 28 U.S.C. 530(D), which states the Justice Department must inform Congress whenever it determines to ”refrain (on the grounds that the provision is unconstitutional) from defending or asserting, in any judicial, administrative, or other proceeding, the constitutionality of any provision of any Federal statute.”